• Korean Journal of Bronchoesophagology
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• v.7 no.2
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• pp.128-139
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• 2001

The purpose of this study was to review the literatures of experimental tracheal reconstruction. Although there have been significant advancements in the surgical treatment of the long circumferential tracheal injuries, there still has been a difficult problem with high morbidity and mortality. The method for tracheal reconstruction after circumferential resection is preferred end-to-end anastomosis for defects up to 6 cm in length, but larger tracheal defects require the use of tracheal allograft, various artificial prosthesis or autogenous organs. The tracheal allotransplantation has been widely used as there was significantly improved the method of surgical technique, preservation and immunosuppression. But it has been limited by a number of factors such as few donor, limited use of immunosuppressant, delayed revascularization and re-epitheliazation. Experimental studies on the tracheal prosthesis have a long history and they tried to use silicone, polytetrafluoroethylene, polypropylene mesh, Dacron, Marlex mesh, external or internal stents. Other experimental studies were reported the use of autogenous tissues that were cartilage. jejunum, aorta, skin, muscle, periostium or esophagus. But a great variety of these protheses have been resulted unsatisfactory in a significant Proportion of cases. Alternatively, the tissue-engineering technique has showed a new approach to reconstruct trachea and much progress in tissue-engineering bas been made recently. In conclusion, although the tracheal allotransplantation and the use of prosthesis and allograft have been reported a lot of limitation to overcome, we could sooner expect good result of ideal tracheal prosthesis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.5
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• pp.402-407
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• 2010

Introduction: The planning of implant surgery is an important factor for the implant prosthesis. Stereolithographic (SLA) surgical stents based on a computer simulation are quite helpful for clinicians to perform the surgery as planned. Although many clinical and technical trials have been performed for computed tomography (CT)-guided implant stents to improve the surgical procedures and prosthetic treatment, there are still many problems to solve. We developed a system of a surgical guide based on 3 dimensional (3D) CT for implant therapy and achieved satisfactory results in the terms of planning and operation. Materials and Methods: Fifteen patients were selected and 30 implant fixtures were installed. The preoperative CT data for surgical planning were prepared after obtaining informed consent. Surgical planning was performed using the simulation program, Ondemend3D In2Guide. The stents were fabricated based on the simulation data containing information of the residual bone, the location of the nerve, and the expected design of the prostheses. After surgery with these customized stents, the accuracy and reproducibility of implant surgery were evaluated based on the computer simulation. The data of postoperative CT were used to confirm this system using the image fusion technique and compare the implant fixtures between the planned and implanted. Results: The mean error was 1.18 (${\pm}0.73$) mm at the occlusal center, 1.23 (${\pm}0.67$) mm at the apical center, and the axis error between the two fixtures was $3.25^{\circ}C$ (${\pm}3.00$). These stents showed superior accuracy in maxilla cases. The lateral side error at the apical center was significantly different from the error at the occlusal center but there were no significant differences between the premolars, 1st molars and 2nd molars. Conclusion: SLA surgical stents based on a computer simulation have the satisfactory accuracy and are expected to be useful for accurate planning and surgery if some errors can be improved.

• The Journal of Advanced Prosthodontics
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• v.5 no.1
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• pp.67-72
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• 2013

Traumatic defects are mostly accompanied by hard and soft tissue loss. This report describes the surgical and prosthetic treatment of a patient with post-traumatic mandibular defect. A split-thickness skin graft was performed prior to implant placement and prefabricated acrylic stent was placed to hold the graft in place. The esthetic and functional demands of the patient were fulfilled by implant-supported screw-retained fixed prosthesis using CAD-CAM technology.

• Journal of Korean Dental Science
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• v.14 no.1
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• pp.32-39
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• 2021

'Crossed occlusion' is the condition in which occlusal intercuspation is lost when several teeth on upper and lower jaw remain. This report describes a clinical case in which a patient had two upper-left posterior teeth and two lower-right posterior teeth; typically known as left-right crossed occlusion. Considering the patient's general condition and financial situation, the treatment plan included placement of two implants on each jaw against the remaining teeth using surgical guide. To find out the ideal position of implants, digital diagnostic wax-up was preceded by superimposing the cast and cone beam computed tomography image, which was aided with radiographic stents. The consequent surveyed implant bridge provided stable vertical stop for fabrication of the implant assisted removable partial dentures. The patient was satisfied with the functionality and esthetics of definitive prosthesis.

• Korean Journal of Radiology
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• v.1 no.3
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• pp.169-171
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• 2000

In order to relieve mechanical obstruction caused by rectal carcinoma, a bare rectal stent was inserted in the sigmoid colon of a 70-year-old female. The procedure was successful, and for one month the patient made good progress. She then complained of abdominal pain, however, and plain radiographs of the chest and abdomen revealed the presence of free gas in the subdiaphragmatic area. Surgical findings showed that a spur at the proximal end of the bare rectal stent had penetrated the rectal mucosal wall. After placing a bare rectal stent for the palliative treatment of colorectal carcinoma, close follow-up to detect possible perforation of the bowel wall is necessary.

• Journal of Chest Surgery
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• v.43 no.1
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• pp.100-103
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• 2010

We report her on a rare case of a renal stent that migrated into the right ventricle in a patient with nutcracker syndrome. A 29-year-old woman was admitted to the hospital and she was suffering from flank pain. The computed tomography of the abdomen demonstrated that the left renal vein was compressed between the abdominal aorta and the superior mesenteric artery (nutcracker syndrome). A self expandable stent was placed across the left renal vein for treating her nutcracker syndrome. The next day after the procedure, the follow up chest radiograph showed that the displaced stent had migrated into the right ventricle. After percutanous endovascular stent removal had failed, the stent was ultimately removed by performing cardiac surgery. At the $6^{th}$ postoperative month, there have been no abdominal or cardiac symptoms.

• Applied Chemistry for Engineering
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• v.29 no.5
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• pp.497-502
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• 2018

The coronary artery disease (CAD) is rapidly increasing such as angina pectoris and atherosclerosis. The CAD is induce by cholesterol and calcium like plaque absortion to artery wall. The percutaneouss coronary intervention is non-invasive treatment that narrowed-artery is expand by using balloon catheter and bare metallic stent. The metallic stents have been effective in reducing the dead by coronary artery disease, but the permanent presence of the metallic stent has been associated with persistent inflammation, and incidence of late thrombosis. Therefore, development bioresorbable vascular scaffold (BRS) is rapidly increasing for treatment of long-term complications and arterial restenosis by permanentmetal prosthesis such as stent. The review discusses the BRS trend for successfully development.